Eyewear keystone feature



FIG. 1 is a perspective view of a pair of eyewear showing the new design for an eyewear keystone feature;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view of a pair of eyewear showing the new design, the right side view being a mirror image thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The broken lines form no part of the claimed design, and any shading is provided to illustrate contour only and is not an indication of texture, gloss, etc. 

The ornamental design for an eyewear keystone feature, as shown and described. 